BRING THE MAPLE SYRUP and sugar to a boil in a small non-aluminum pan, then cook for 3 minutes. Add the cranberries and cook until their skins burst and they begin to pop, 6-to-8 minutes, or slightly longer if they are frozen. Cut the butter into 3 pieces. Remove the pan from the heat and whisk in the butter, 1 piece at a time, waiting until each is incorporated before adding another. Add the bourbon. Sauce can be served immediately or refrigerated for up to a week. Reheat gently and thin with 2 to 3 tablespoons water before serving.